Rust custom error

lib.rs

pub mod custom {
    use thiserror::Error;

    #[derive(Debug, Error)]
    #[error("{message:} ({line:}, {column:})")]
    pub struct JsonError {
        pub message: String,
        pub line: usize,
        pub column: usize,
    }
}

main.rs

use custom_error::custom;
use std::fmt;

#[derive(Debug, Clone)]
pub struct JsonError {
    pub message: String,
    pub line: usize,
    pub column: usize,
}

impl fmt::Display for JsonError {
    fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
        write!(f, "{} ({}:{})", self.message, self.line, self.column)
    }
}

impl std::error::Error for JsonError {}

fn main() {
    let x: usize = 100;

    match TryInto::<u8>::try_into(x) {
        Ok(y) => println!("{}", y),
        Err(e) => println!("{}", e),
    }

    println!("{:?}", test());
}

fn test() -> Result<(), custom::JsonError> {
    Err(custom::JsonError {
        message: "hoge".to_string(),
        line: 1,
        column: 1,
    })
}